/*-
 * Copyright (c) 2011 Felix Fietkau <nbd@openwrt.org>
 * Copyright (c) 2010 Isilon Systems, Inc.
 * Copyright (c) 2010 iX Systems, Inc.
 * Copyright (c) 2010 Panasas, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice unmodified, this list of conditions, and the following
 *    disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef _LINUX_LIST_H_
#define _LINUX_LIST_H_

#include <stddef.h>
#include <stdbool.h>

#define prefetch(x)

#ifndef container_of
    #define container_of(ptr, type, member)                           \
        ({                                                            \
            const __typeof__(((type *)NULL)->member) *__mptr = (ptr); \
            (type *)((char *)__mptr - offsetof(type, member));        \
        })
#endif

struct list_head
{
    struct list_head *next;
    struct list_head *prev;
};

#define LIST_HEAD_INIT(name) \
    {                        \
        &(name), &(name)     \
    }
#undef LIST_HEAD
#define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name)

static inline void
INIT_LIST_HEAD(struct list_head *list)
{
    list->next = list->prev = list;
}

static inline bool
list_empty(const struct list_head *head)
{
    return (head->next == head);
}

static inline bool
list_is_first(const struct list_head *list,
              const struct list_head *head)
{
    return list->prev == head;
}

static inline bool
list_is_last(const struct list_head *list,
             const struct list_head *head)
{
    return list->next == head;
}

static inline void
_list_del(struct list_head *entry)
{
    entry->next->prev = entry->prev;
    entry->prev->next = entry->next;
}

static inline void
list_del(struct list_head *entry)
{
    _list_del(entry);
    entry->next = entry->prev = NULL;
}

static inline void
_list_add(struct list_head *_new, struct list_head *prev,
          struct list_head *next)
{

    next->prev = _new;
    _new->next = next;
    _new->prev = prev;
    prev->next = _new;
}

static inline void
list_del_init(struct list_head *entry)
{
    _list_del(entry);
    INIT_LIST_HEAD(entry);
}

#define list_entry(ptr, type, field)       container_of(ptr, type, field)
#define list_first_entry(ptr, type, field) list_entry((ptr)->next, type, field)
#define list_last_entry(ptr, type, field)  list_entry((ptr)->prev, type, field)

/**
 * list_first_entry_or_null - get the first element from a list
 * @ptr:	the list head to take the element from.
 * @type:	the type of the struct this is embedded in.
 * @member:	the name of the list_head within the struct.
 *
 * Note that if the list is empty, it returns NULL.
 */
#define list_first_entry_or_null(ptr, type, member) ({         \
    struct list_head *head__ = (ptr);                          \
    struct list_head *pos__  = READ_ONCE(head__->next);        \
    pos__ != head__ ? list_entry(pos__, type, member) : NULL; \
})

/**
 * list_next_entry - get the next element in list
 * @pos:	the type * to cursor
 * @member:	the name of the list_head within the struct.
 */
#define list_next_entry(pos, member) \
    list_entry((pos)->member.next, typeof(*(pos)), member)

/**
 * list_prev_entry - get the prev element in list
 * @pos:	the type * to cursor
 * @member:	the name of the list_head within the struct.
 */
#define list_prev_entry(pos, member) \
    list_entry((pos)->member.prev, typeof(*(pos)), member)

#define list_for_each(p, head) \
    for(p = (head)->next; p != (head); p = p->next)

#define list_for_each_safe(p, n, head) \
    for(p = (head)->next, n = p->next; p != (head); p = n, n = p->next)

#define list_for_each_entry(p, h, field)                                  \
    for(p = list_first_entry(h, __typeof__(*p), field); &p->field != (h); \
        p = list_entry(p->field.next, __typeof__(*p), field))

#define list_for_each_entry_safe(p, n, h, field)              \
    for(p = list_first_entry(h, __typeof__(*p), field),       \
    n     = list_entry(p->field.next, __typeof__(*p), field); \
        &p->field != (h);                                     \
        p = n, n = list_entry(n->field.next, __typeof__(*n), field))

#define list_for_each_entry_reverse(p, h, field)                         \
    for(p = list_last_entry(h, __typeof__(*p), field); &p->field != (h); \
        p = list_entry(p->field.prev, __typeof__(*p), field))

#define list_for_each_prev(p, h)         for(p = (h)->prev; p != (h); p = p->prev)
#define list_for_each_prev_safe(p, n, h) for(p = (h)->prev, n = p->prev; p != (h); p = n, n = p->prev)

static inline void
list_add(struct list_head *_new, struct list_head *head)
{
    _list_add(_new, head, head->next);
}

static inline void
list_add_tail(struct list_head *_new, struct list_head *head)
{
    _list_add(_new, head->prev, head);
}

static inline void
list_move(struct list_head *list, struct list_head *head)
{
    _list_del(list);
    list_add(list, head);
}

static inline void
list_move_tail(struct list_head *entry, struct list_head *head)
{
    _list_del(entry);
    list_add_tail(entry, head);
}

static inline void
_list_splice(const struct list_head *list, struct list_head *prev,
             struct list_head *next)
{
    struct list_head *first;
    struct list_head *last;

    if(list_empty(list))
        return;

    first       = list->next;
    last        = list->prev;
    first->prev = prev;
    prev->next  = first;
    last->next  = next;
    next->prev  = last;
}

static inline void
list_splice(const struct list_head *list, struct list_head *head)
{
    _list_splice(list, head, head->next);
}

static inline void
list_splice_tail(struct list_head *list, struct list_head *head)
{
    _list_splice(list, head->prev, head);
}

static inline void
list_splice_init(struct list_head *list, struct list_head *head)
{
    _list_splice(list, head, head->next);
    INIT_LIST_HEAD(list);
}

static inline void
list_splice_tail_init(struct list_head *list, struct list_head *head)
{
    _list_splice(list, head->prev, head);
    INIT_LIST_HEAD(list);
}

int insert_into_ids(char *dev_id, struct list_head *info_list);
int find_id_from_ids(char *dev_id, struct list_head *info_list);
int clear_dev_ids(struct list_head *info_list);

#endif /* _LINUX_LIST_H_ */
